(For other uses, see Nose (disambiguation).)(This article is about noses in general. For the article about noses in humans, see human nose.) Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared with the digestive system, and then into the rest of the respiratory system. In humans, the nose is located centrally on the face and serves as an alternative respiratory passage especially during suckling for infants. On most other mammals, it is located on the upper tip of the snout.